iirc it's generated from a script in asterisk, with the delay and tone durations set "short" (I think it was the minimum EIA/TIA DTMF mark/space numbers, not sure.)
My phone system was Google Voice, through an SIP bridge with Obihai (now defunct/discontinued). Asterisk then made the SIP connection and rang my other phones, a Lucent Partner ACS for my landlines, cellphones, ATAs and forwarding numbers, also over SIP.
Most of the hardware was lost in the housefire last year. This recording was from early-mid 2020 or so.
Comments
From a comment on the blog post:
https://cohost.org/sirocyl/post/2891449-i-broke-ikea#comment...